UPDATE: (5pm - 17th July) Following further medical advice Dallin Watene-Zelezniak will not require surgery, however his return to the field is still indefinite at this stage.
Penrith Panthers can report fullback Dallin Watene-Zelezniak has suffered primary spontaneous pneumothorax, resulting in a collapsed lung, and was hospitalised on Tuesday.
The genetic condition occurs when the rupture of small sacs of air in the lung tissue leads to the abnormal accumulation of air in the space between the lungs and the chest cavity.
It is unclear whether this episode was triggered by a physical blow suffered in Penrith's match against Sydney Roosters on Saturday.
Watene-Zelezniak and the Panthers are currently seeking further medical advice to determine the best course of action moving forward.
At this stage Watene-Zelezniak is sidelined indefinitely.